Masks, in particular gas masks or self contained breathing apparatuses, have become increasingly complex.
These masks form an integral seal around the user's face to prevent vapors in the atmosphere from reaching the user's eyes, nose, mouth or skin surrounded by the mask. A full mask, or full face mask, will protect all the numerated parts. A partial mask, or half mask, will protect the eyes and the skin surrounded by the mask or the nose, mouth and skin surrounded by the mask.
For extreme and unpredictable conditions, such as those experienced by firefighters, police officers, and military; the full face mask is preferred. Because the masks may be worn for an extended period of time, several modifications have been made to allow the user to communicate and even receive nutrients and water without removing the mask. The full mask usually has at least one air filter port to which a filter is attached. The filter removes the contaminants from the air and allows the user to breathe uncontaminated air. In the case of a self contained apparatus, the air is provided from a bottle and no filter is needed.
Over time, the gas mask has evolved to include physical and electronic ports. For example, Avon Products series 50 (manufactured in Cadillac, Mich.), has a tube and twistable spout for the user to receive a liquid without breaking the seal. The Avon products 50, 51, and 53 series of masks use an outsert lens as described in the specification below. Some of Avon Products masks also have a communications device for the user to speak into and the sound is audibly heard outside the mask or sent to a transmission device for reception at another spot.
Masks prior to the Avon Products M50 began including a transmission device to be attached to the port of a dual filter mask, using one of the ports for transmission limits the use time between changing filters.
There is a need for even more devices attached or mounted to the mask. Because the attachment of devices to the mask cannot break the seal integrity of the mask or interfere with hoods worn to cover all the exposed skin, including the mask, unique, inventive devices are needed.